If you’re unfamiliar, a ‘hook’ is an intriguing part/idea/element of your story that gets people’s attention and makes them want to buy and read your book. It’s your cool idea.
For example: “My story is about three guys having a midlife crisis who decide to start a college fraternity.” The text I put in italics is the hook — the cool idea that sucks you in. Another hook example: “Imagine star-cross’d lovers in the vein of Romeo & Juliet — except instead of two noble families in 1500s Italy, my story follows Barbary pirates battling the British Navy in the 19th century Caribbean.” Having another spin on Romeo & Juliet is nothing new (“typical is the enemy”), but a Juliet who’s the daughter of a British Navy captain, and a Romeo who’s the son of the cruelest pirate on the seven seas? Now that’s a hook. I want to know more!
Anything unique or different or special about your main character and storyline should show up in a pitch. Set your work apart from the other many pitches that an agent sees during a given week.
It’s not a secret that hooks are your best friend when enticing ANYONE to read your book – much less a literary agent who reads books all day every day for a living.
Tell an agent about your main character’s quirks and odd plot points. Remember – typical is the enemy!